A basic description of the mechanism of CT (computed tomography) scans for medical use in remote sensing. Part of the A Level Physics revision series.

A basic description of the mechanism of CT (computed tomography) scans for medical use in remote sensing. Part of the A Level Physics revision series.

DrPhysicsA, CT means Computerized axial Tomography right?or does Computed Tomography mean the same?

Wait a minute! Is he saying roughly that the image is created using a matrix?

This was really helpful. Thanks!

im not getting perfectly that why you divided by 3???

i just did this today at school.thank you soo much i understand it way better now!

keep up the good work,you got another sub 🙂

Awesome one

i didn't follow that at all, you explained it well, i must just be dumb.

Thank you so much for making this video, it wasn't completely clear to me before but now I fully understand!

What kind of computer of processor would a CT scanner use to add all this up? So much computation needed for just one voxel, insane !

hats off!

y u no longer make videos u have soo many subscribers

What a very clever presentation – so often they are fudged and nobody, maybe including the presenter, comes out understanding. Thank you for this – and well done!

thank you for these information

is he washing ? or is it a blender?

What is the name of this method ?

Dota 2 logo, anyone?

by the way, are you boiling water when you were doing the video?

What is a voxel? I need a scientific definition plz.

wow so ct is using x ray

and it builds a 3d image

that is so interesting

thanks !

thanks a loooooooot, sir! you r a life saver

This explanation is simply the best one i have seen. you're doing a great job in explaining all these things. you are truly a life-saver

at 10:07 do we just divide by a common factor; such as for the this example the common factor was 3?

Thanks

Are yu Fuking riding a plane?

Mentally Fucked

Doing an offset (subtracting 16) at the end is actually here a way of doing a high pass filter. Since there are only two possible frequencies for each axis, then subtracting lowers DC (frequency 0) which makes the other frequency (nyquist) relatively higher. Only works in this particular case.

Hi, one of the question mentioned "background reading". May I know what that is?

The algorithm is fantastic! Thanks for explaining this!

Great! explained very well. Thanks

Why is the background reading the sum of attenuation for one scan??? And why is everything divided by 3 in the final step?????

What kind of brain comes up with this……makes me feel stupid….well done chaps. You both earned your 1979 Noble prizes

How does this scale from a 2 by 2 to an N by N grid?

Who came up with that algorithm?! And why?

Hey,

Thanks for the clear and concise explanation.

I have 2 queries.

1. Are the computed voxel values directly interpretated as image pixel intensities which is what we see as the CT image?

2. As per my understanding, the detector will record the intensities of the received beam whereas the numbers that you mention in the voxel's are attenuation coefficients. So, more the attenuation coefficient or a voxel lesser will be the intensity recorded. What exactly do the summed values 7, 9, etc. represent? Are they the attenuation coefficients or the intensities recorded by the detector?

Thanks in advance!

thank you

I finally understand why my physics lecturer is a pure rubbish after watching this 👍

Wow

awesome

Thank you! Great revision video. ^_^

THANK YOU SO MUCH!

Hello thank you! And how is the final results of the matrix transformed in an image like the black pages the laboratories give you as fault ? Thank you

very helpful

Sir can u please make a video about iterative reconstruction

Very nice description. But I think you need to emphasize that you solver the

forwardproblem. That is, given the voxel absorption values, find the absorptions of the 4 beams. Actually going into hospital and getting a CT scan and reconstructing the voxel values from it is theinverseproblem. Is the inverse solution unique? Often they are not.After all these years, it helped me to clear my doubts. Thank you!

Well…. If I take a 3by 3 box then from how many angles I need to project??? Plz reply… Is there any formula for that..?

I'm puzzled by the apparent additive nature of the voxels rather than multiplicative. If I shine a light through a two filters that individually block out 50% of the light, I'd expect that combining the two would block out 1 – .5*.5 = 75% of the light, not 100%. Do XRays operate differently, or is the percentage of X rays blocked so small that using addition is an acceptable approximation for multiplication?

What do you call this kind of CT reconstruction?? Because we have different kinds of CT reconstruction – Back projection, Iterative, and Analytic Method. What is this kind?